Lighting systems in the prior art are typically formed by interconnecting, via a communications system, a plurality of lighting fixtures and providing for operator control of the plurality of lighting fixtures from a central controller. Such lighting systems may contain multiparameter light fixtures, which illustratively are light fixtures having two or more individually remotely adjustable parameters such as focus, color, image, position, or other light characteristics. Multiparameter lighting fixtures are widely used in the lighting industry because they facilitate significant reductions in overall lighting system size and permit dynamic changes to the final lighting effect. Applications and events in which multiparameter lighting fixtures are used to great advantage include showrooms, television lighting, stage lighting, architectural lighting, live concerts, and theme parks. Illustrative multi-parameter light devices are described in the product brochure entitled “The High End Systems Product Line 2001” and are available from High End Systems, Inc. of Austin, Tex.
A variety of different types of multiparameter light fixtures are available. One type of advanced multiparameter lighting fixture is an image projection lighting device (“IPLD”). Image projection lighting devices of the prior art typically use a light valve or light valves to project images onto a stage or other projection surface. A light valve, which is also known as an image gate, is a device for example such as a digital micro-mirror (“DMD”) or a liquid crystal display (“LCD”) that forms the image that is projected. Either a transmissive or a reflective type light valve may be used. U.S. Pat. No. 6,057,958, issued May 2, 2000 to Hunt, incorporated herein by reference, discloses a pixel based gobo record control format for storing gobo images in the memory of a light fixture. The gobo images can be recalled and modified from commands sent by a control console. A pixel based gobo image is a gobo (or a projection pattern) created by a light valve like a video projection of sorts. U.S. Pat. No. 5,829,868, issued Nov. 3, 1998 to Hutton, incorporated by reference herein, discloses storing video frames as cues locally in a lamp, and supplying them as directed to an image gate to produce animated and real-time imaging. A single frame can also be manipulated through processing to produce multiple variations. Alternatively, a video communication link can be employed to supply continuous video from a remote source.
IPLDs of the prior art use light from a projection lamp that is sent through a light valve and focused by an output lens to project images on a stage or a projection surface. The control of the various parameters of the IPLDs is affected by an operator using a central controller. In a given application, a plurality of IPLDs are used to illuminate the projection surface, with each IPLD having many parameters that may be adjusted by a central controller to create a scene.
IPLDs used in an entertainment lighting system can produce many colorful images upon the stage or projection surface. IPLDs may project images onto the projection surface such as still images, video images and graphic images. The term “content” is a general term that refers to various types of creative works, including image-type works and audio works. Content is typically comprised of still images, video images or loops and computer graphical images.
The Catalyst (trademarked) DL1 image projection lighting device manufactured by High End Systems of Austin Texas incorporates a video projector into an environmentally protective housing that can be remotely positioned to projected images to different locations upon the stage or projection surface. A personal computer is used as a server that provides the images to the DL1. A lighting controller sends command signals over a communication system to control the selection of images from the server to the projector as well as control the various functions of the DL1 and the position of the image on the projection surface.
The content or video images may reside as image data stored at the central controller or the content or images may reside as data stored in the memory of the IPLD. The content (also can be referred to as video or still images herein referred to as just images) can be created by a graphics artist on a personal computer. The graphics artist may use programs such as Adobe Photoshop (trademarked) manufactured by Adobe Systems of San Jose, Calif. of Final Cut Pro (trademarked) manufactured by Apple Computer of Cupertino, Calif. to create images.
A central control system for controlling a plurality of IPLDs is described in U.S. patent application titled: “Method and apparatus for controlling images with image projection lighting devices” filed Jul. 29, 2002 by inventor Richard S Belliveau, Ser. No. 10/206,162 and is incorporated herein for reference.
It has been found that when a graphics artist creates images that can be used as content for many applications, the artist is not always concerned with the optimal performance of the images as projected by an IPLD. Often times the graphics artist may not have advanced knowledge of how the images need to be produced for optimum performance when projected by an IPLD. For example the images created by the graphics artist may look fine on the artist's CRT or LCD screen but the images may not reach the maximum brightness capability of the IPLD when projecting onto the projection surface.
The images that were created by the graphics artist when projected by an IPLD onto a projection surface may not reach the full brightness potential of the IPLD. It's also possible that the darkest part of the images may not reach the best black level potential of the IPLD. When images projected by an IPLD fail to reach the full brightness level or best black level the visual performance of the IPLD suffers in the eyes of the audience. There is a need to create a system for optimizing the images that are projected by IPLDS onto the projection surface. The system should optimize the images projected by an IPLD to be projected at maximum brightness levels. The system may also insure that the darkest components of the images that are projected by an IPLD obtain the best black level.